மேலும்கீழுமாகத் தலையை ஆட்டுதல்

A yellow smiley face with closed eyes and a mouth with a subtle upward curl, shown with motion lines indicating that the smiley is shaking its head up and down vertically. 

This is intended to depict a nodding gesture, which is commonly (but not universally) used to indicate agreement, acceptance, or acknowledgment.